Lens grinding and polishing machine



May 1-8,' 1943 E. M. LONG LENS GRINDING AND POLISHING MACHINE 'Filed Nov 27, 1941 5 Sheets-Sheet 1 brig INYENTUR ELI M Luna EYE? A'r'r DRHEY y 1943' E.' M LONG n 2,319,417

LENS GRINDING: AND POLISHING MACHI NE I I Filed NOV. 27, 1941 3 Sheets-Sheet 2 May 1 8, 1943 E. M. LONG LENS GRINDING AND POLISHING MACHINE Filed Nov. 27; 1941 3 Sheets-Sheet 3 INVENT an [L1 M Lam:

Patented May 18, 1943 2,319,417 LENS GRINDING-AND POLISHING MACHINE Eli M. Long, Geneva, N. Y., assignor to Shuron Optical Company, Inc., Geneva, N. Y., a corporation of New York Application November 27, 1941, Serial No. 420,716.

12 Claims.

structure, develop an excessive amount of vibra- H tion as is the case in lens grinding and'polishing machines where relative movement of a lens'and a lap or grinding surface is produced by two .reciprocative movements operating at. relatively high speeds and preferably at substantially right angle to each other. It is, of course, always de sirable that such machines operate quietly and with a minimum amount of vibration to maintain as high a degree of efficiency of the machine as possible. Furthermore, lens forming machines are often placed in ofice buildings or other public places Where tenants such as doctors, lawyers and others desiring quiet surroundings are located in rooms adjacent to or directly below a room containing one or more of these machines. a

This is an additional reason why it is most desirable that lens grinding and polishing machines or the like operate as smoothly and quietly as possible.

The main object of this invention is to provide a lens grinding and polishing machine or other similar instrument of the above mentioned character with a vibration dampener by which vibratory movement of the machine or instrument is reduced to a minimum.

Lens grinding and polishing machines which utilize two reciprocative movements to efiect grinding and polishing of lenses often have a continuous variation movement, commonly known as a third or break-up movement. This movement operates in conjunction with one or each of the reciprocative movements to continually vary the length of the stroke or path of relative movement of the lens and grinding surfaces to thereby materially lengthen each cycle of said relative movement and produce lenses or other objects having highly polished surfaces which are free from deformations and waves.

Another object of this invention is to provide a machine of the character described employing said member.

a reciprocating member and means for reciproeating said member with a constantly changing stroke with a vibration dampener which functions with a variable degree of effect upon the reciprocating member in accordance with variations in the stroke and speed of operation of In other words, means are provided whereby an efficient dampening effect is produced under all operating conditions, so as to obtain maximum efliciency both respecting the speed of operation of the machine and the ability thereof to produce work of highest quality.

I attain these objects by mechanism illustrated in the accompanying drawings, in which:

Figure 1 is a plan view of a lens grinding and polishing machine having a vibration dampener associated therewith embodying the various features of this invention, a small portion only of the frame or housing for the mechanism being shown.

Figure 2 is a detail vertical sectional view taken substantially on line 22, Figure 1, showing the greater portion of the mechanism in front ele- VatlOn;

Figure 3 is an enlarged detail transverse vertical sectional view taken substantially on line 3--3, Figure 1, showing more particularly my vibration dampener and the manner in which the same is connected with the drive and driven members of the machine.

7 Figure 4 is a vertical sectional view through the vibration dampener counterweight taken substantially on line 4-4, Figure 3.

Figure 5 is a detail longitudinal sectional view taken substantially on line 5-5, Figure 1, showing a break-up or third movement associated with the drive mechanism for producing a reciprocative movement whereby a continuous variation in the length of the stroke of said reciprocative movement is obtained.

Figures 6 and 7 are vertical sectional views taken respectively on lines G--6 and 1-1, Figure 5. V

Figure 8 is a detail longitudinal sectional view through one of the auxiliary drive mechanisms taken on line.83, Figure 5.

Figure 9 is an outer face View of the drive mechanism shown in Figure 8.

In order to illustrate my invention, I have shown in the drawings a lens grinding and polishing machine of the type shown in my Patent No. 2,159,620, issued May 23, 1939. The structure shown in this patent comprises two lens grinding couples or units, each consisting of a lens holder and a grinding lap. The grinding couples are operated in synchronism by a drive mechanism in which is combined two reciprocative movements and two break-up movements operating in conjunction with the reciprocative movements.

In my present invention I have shown a vibration dampener operatively connected with one of the reciprocative movements of the drive mechanism in such a manner that the inertia forces due to reciprocation are substantially neutralized. Furthermore, the construction is such that any variation in the reciprocative movement produced by the break-up movement results in a corresponding variation in the operation of the vibration dampener and thereby maintains a maximum vibration dampening effect for all variations incident to mechanical variation produced by the drive mechanism.

The machine as illustrated in the drawings comprises a pair of actuating or pressure arms It by which one. of the members of each lens grinding couple is operated with respect to the other member. The lens grinding couples are omitted in the drawings in as much as they may be of any suitable construction and do not particularly pertain to the main features of this invention. However, the arms In as shown are adapted to operate the lens holder with respect to the grinding lap. These arms are operatively connected with a carrier mechanism H which in this instance comprises a lower rock frame l2, an upper floating frame or carriage i3 supported in substantially a horizontal position above the lower frame by a pair of vertically disposed supporting frames It, and a pair of supplemental rock frames l5; The lower frame I2 is pivotally supported upon the bottom of the case or housing H of the machine as by pins |8 carried by upwardly projecting lugs l9 formed on said bottom and extending into bearing members 2i mounted in the ends of the frame l2. The vertical supporting frames M are bifurcated at their lower and upper ends for receiving frames 2 and I3 between them and are pivotally connected as at 22 to the lower frame l2 adjacent the ends of said frame. The upper ends of the frames I4 are pivotally connected as at 23 with the floating frame IS. The supplemental frames I5 are arranged at opposite sides of the center of the frame l3, and are each pivotally connected thereto as indicated at 24 and 25 so as to swing about a common axis extending at substantially right angles to the axes of rocking movement of the frames l4 and parallel with the pivotal axis of the frame l2. The pressure arms I are rotatably journaled in suitable bearing members 21 mounted in the auxiliary frames l as indicated in Figures 1 and 2 of the drawings, said arms being maintained in spaced substantially parallel relation with respect to each other to rotate about substantially horizontally disposed axes extending in right angular relation to the axis of rocking movement of frame The carrier mechanism I is reciprocated by a main drive mechanism and two auxiliary drive mechanisms operated by the main drive mechanism. The main drive mechanism, as shown in the drawings, is mounted in the case or housing ll 7 connected to said shaft exteriorly of the housing H.

An auxiliary drive mechanism 33 is actuated by shaft 39 to reciprocate a portion of the carrier mechanism in one direction. This drive mechanism 33 comprises a shaft 36 also mounted in the transmission housing 3| and which extends outwardly from the inner end of said housing, shaft 34 being operatively connected by suitable gears (not shown) to the shaft 36 to be rotated thereby. The shaft 34 has secured to the end thereof projecting from the housing 3| a drive block 35 which is provided with a groove or recess 36 extending transversely therethrough. Mounted in the recess 35 is a supporting head 3'! which has connected to the outer side thereof a crank shaft 38. The head 31 is slidably maintained in the recess 36 for movement longitudinally thereof by a pair of gibs 39 secured to the drive block 35 as illustrated in Figures 6 and '7. The head 3? has a recess 3'! in the inner face thereof which receives a swivel stud connected with the head 35 adjacent one end of the recess 36. The head 37 is also provided With a screw member 4| which extends through a threaded opening provided in said head at one end of the recess 37 in screw threaded engagement therewith. The inner end of the screw 4| is rotatably anchored to the stud 49 by a pin and groove structure 32 as shown in Figure 5.

The shaft 38 has rotatably mounted thereon an eccentric sleeve 65 which is positioned between the head 31 and a gear housing 4% secured to the shaft 38 adjacent the outer end thereof. The end of the sleeve it: which is adjacent the housing '65 has secured thereto a gear 41' arranged concentric with the shaft 38. This gear i? is mounted in a recess 49 provided in the housing 45 and has meshing engagement with a pinion 53 also mounted in the recess 49 as shown in Figure 8. The pinion 5:! is connected with a stub shaft 5| which extends through a bearing provided in the central web portion at of the housing 46 and extends into a second recess 53 provided in the housing 58 at the outer side thereof. Mounted on the shaft 5| is a gear 55 similar to the gear Iii and which has meshing engagement with a second pinion 55 positioned in the recess 53 and rotatably mounted on the reduced end 56 of the crank shaft 38. Secured to the pinion 55 is an arm 58 which extends radially from the shaft portion 55 into engagement with a stop pin 59 carried in this instance by an eccentric 66 which will hereinafter be more fully explained. The arm S8 is provided with a slot 58 which extends inwardly from the outer end thereof and slidably receives the pin 59 therein. The function of the arm 58 and pin 59 is to maintain the pinion 55 against rotation with respect to its axis as said pinion and the shaft 38 revolve about the axis of shaft 34.

The inner end portion of the eccentric sleeve 55 has a ball bearing member 5| mounted there on in eccentric relation to the axis of the shaft 38. The bearing 6| has mounted thereon the eccentric strap 82 of the hereinbefore mentioned eccentric 6d. The eccentric 5G is provided with an eccentric rod 64 rotatabiy mounted at its outer end on a pin '55 carried by one arm 68 of a bell-crank lever B? which in turn is fulcrumed on a pin 63 secured to an arm 68 extending rearwardly from the housing 3:. The other arm 16 of the bell-crank lever 57 has -secured to the outer end thereof a pin ll upon which is rotatably mounted a pivot block 12 which in. turn rotatably supports one end of a connecting rod or pitman 13. The rod or pitman 13 extends forwardly from the block 12 and has the forward end thereof rotatably mounted in a'second pivot block 14. Block '14 is rotatably connected with the floating frame 13 substantially midway between the ends thereof by a pair of forwardly projecting lugs 15, as shown more particularly in Figures 1 and 2. It will now be observed that during rotation of the shaft 34 the eccentric or crank shaft 38 revolves about the axis of the shaft 34 in more or less eccentric relation thereto depending upon the position of the head 31 with respect to the drive block 35. It therefore follows that the eccentric member 60 will transmit motion from shaft 38 to thebell-crank lever 61, producing rocking movementof said lever. This rocking movement of the lever 61 produces a corresponding reciprocating movement of the connecting rod 13 and, therefore, of the floating frame It and the rock frame l2 about the axis of pins 18. During the revolving movement of the crank shaft 38 the eccentric sleeve is rotated with respect to said shaft due to the action of the train of gears comprising the pinion 55, gear 54, pinion '56 and gear 41 This revolving of the eccentric sleeve ,45 gradually changes the axis of the, eccentric sleeve and bearing 6| with respect to the axis of the shaft 38. This variation in the eccentric relation of the sleeve 45 with respect to the shaft 7 construction and material and which is pivotally connected at 19 to the housing I! at the rear of the carrier mechanism II and beneath the crank shaft 38 asillustrated more particularly in Figure 3. The counterweight 1B is connected with the drive mechanism described above for reciprocating the floating frame 13 normal to the axis of the rock frame 12 by means of a link 80 which is pivotally connected at 8| to the counterweight l8 and at 82 to an extension (of the bell-crank lever arm 66. The counterweight I8 is also operatively connected with the carrier mechanism II by means of a spring 84 coiled upon a pair of grooved heads 85 and 8-6. The heads 85 and 86 are provided with stems 85' and 86' respectively. The stem 85' is secured to the counterweight 58 by a stud 81 and screw 88. The other stem 86' is connected with the carrier mechanism H by a stud 89 and a screw 90, stud 89 being connected with the upper end of a vertically disposed arm 9! secured to or made integral with the rock frame .12, as illustrated in Figures 2 and 3. The construction of spring 84 and the connections of the stems 85 and 86 with the counterweight T8 .andythe carrier mechanism -H are such that when the counterweight and the carrier mechanism are in their central positions substantially midway between the ends of the strokes thereof,.said spring is of normal length, neither compressed nor extended. It will be observed that inasmuch as the counterweight 18 is actuated from onearm as 66 of the bell-crank lever while the reciprocative movement of the carrier mechanism II is produced from the other-arm 10 of said bell-crank lever, the reciprocative movement of the weight and mechanism will be in opposed relation to each other. 'It therefore follows that when the counterweight and carrier mechanism are moving from their central positions away from each other the spring 84 will be brought under tension by the expansion there of; and when the counterweight and carrier mechanism are moved from their central positions toward each other, said spring 84 will be compressed. The spring 84, therefore, assists in overcoming the inertia of the counterweight and carrier mechanism at the end of each stroke. Furthermore, the reciprocative movement of the counterweight being opposed to that of the carrier mechanism, said weight will minimizeor substantially neutralize the inertia forces due to reciprocation of the carrier mechanism. Also, it will be observed that any variation in the movement of the bell-crank lever 61 produced by the coaction of the eccentric sleeve 45 and crank shaft 38 upon the movement of the eccentric will be transmitted to the counterweight I8 as well as to the carrier mechanism ll so that the counterweight will reciprocate through a longer a shorter stroke in accordance with the operation of the carrier mechanism and dampen the vibratory action of the mechanism with maximum efficiency.

The drive mechanism for reciprocating the carrier mechanism H just described produces what is generally known as the short or cross strokes of the lenses actuated by the pressure arms ID with respect to the grinding lap. The lenses are 'reciprocated through the long or lengthwise strokes by means of a second auxiliary drive mechanism 95 which is constructed similarly to the drive mechanism 33. This drive mechanism 95 comprises a drive shaft 96 which extends from within the transmission housing 3| where it is operatively connected with the drive shaft 30 through a suitable gear mechanism (not shown) to the outside of the said housing. Secured to the outer end of the shaft 96 is a drive block 91 similar to the drive 'block 35. Slidably connected with the drive block 91 is a crank shaft similar to the crank shaft 38 and which is provided with a head member 98 adjustably connected with the .block 91 in substantially the same manner in which head 31 is connected with the block 35. Mounted upon thecrank shaft carried by the head 91 is a gear housing *99 which has a train of gears similar to those carried by the housing 46, one of said gears being mounted on an eccentric sleeve (not shown) journaled on frame [3 by a ball and socket joint indicated at It will now be observed that when the drive shaft 30 is rotated, the floating frame l3 will be reciprocated through the action of the eccentric I00 in a direction substantially parallel with the axis of rocking movement of the lower frame 12 and therefore at substantially right angles to the reciprocative movement produced by the auxiliary drive mechanism 33.

It is believed that in as much as the construction and operation of the auxiliary drive mech anism '95 is substantially the same as that of the auxiliary drive mechanism 33, it is unnecessary to further describe or illustrate the construction and operation of the drive mechanism 95. However, it will be observed that while I have shown my novel vibration dampener operatively connected with the drive mechanism 33 it may as readily be operatively connected with the drive mechanism 95 for dampening the reciprocative movement of the carrier mechanism H through the lengthwise stroke thereof. that vibration dampeners may be used in conjunction with both of these auxiliary drive mechanisms if it is so desired without departing from the spirit of the invention.

While I have illustrated and particularly described one form of my invention and a specific application thereof, I do not Wish to be limited to the exact construction shown as various changes may be made in the construction and operation of the parts thereof without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. In a machine of the character described having a member mounted for reciprocative movement, in combination, power drive means operatively connected with said member for producing said reciprocation thereof, a counterbalance element supported independently of said member and drive means, means providing a yielding connection between the element and member, separate means providing a substantially rigid connection between the drive means and said element, said latter connecting means including drive and driven members so constructed and arranged with respect to the drive means that said counterbalance element is operated by said drive means in opposed relation to the operation of the recirpocating member for dampening the vi.-

bratory motion produced by the operation of said latter member.

, 2. In a mechanism of the character described having a member mounted for reciprocative movement, a rotary drive shaft, a counterbalance member, means reciprocatively supporting the counterbalance member independently of the reciprocating member, means operatively connecting the drive shaft with the reciprocating member and'with said counterbalance member for actuating the same, said latter means including linkage elements so constructed and arranged that the movements of the members are in reverse direction to each other, and means for overcoming the inertia of said members at the ends of their strokes including a spring operatively connecting the counterbalance member and the reciprocating member to each other, whereby the vibratory actions of said members substantially neutralize each other.

3. In a machine of the character described having a support and a member mounted thereon for reciprocative movement, a counterbalance member spaced from said reciprocating member; means for mounting the counterbalance member on the support to reciprocate with respect to said support; a main drive mechanism on the supper; in spaced relation to said members; means op atively connecting said drive mechanism to members'for producing simultaneous reciproca- 'tive' movement-of said 'members in opposite -di- Also it is obvious rections, said connecting means including a break-up mechanism adapted to cause variations in the reciprocative movements of said members, and a linkage mechanism connecting the breakup mechanism with the members; and separate means including a spring operatively connecting said members to each other of such a character that the inertia force at the ends of the strokes of said reciprocating member are substantially neutralized. f

4. A vibration dampener device for a reciprocating member which com-prises a counterweight mounted independently of said reciprocating member, drive means operatively connected with the reciprocating and counterweight members for simultaneously reciprocating said members in directions opposed toeach other, and means independent of said drive means yieldingly connecting the members to each other, said latter means being of such a character that the movement of one member is opposed by the movement of the other member to neutralize the inertia forces resulting from said reciprocating movemerits thereof.

5. In a lens grinding and polishing machine having a carrier mechanism comprising a pair or" frame members mounted to reciprocate in directions substantially normal to each other, in combination, two drive means, one for each frame member, means operatively connecting the drive means with the frame members for producing said reciproca'tive movements of said members, and a vibration dampener for at least one of said frame members including a counterbalance operatively connected with said latter frame member and with said means connecting the frame member with the corresponding drive means adapted to minimizethe inertia forces due to reciprocation of said latter frame member.

6. In a lens grinding and polishing machine having a carrier mechanism comprising a pair of frame members mounted to reciprocate in directions substantially normal to each other, in combination, two drive means, one for each frame member, means operatively connecting th drive means with the frame members for producing said reciprocative movements of said members', the connecting means for at least one of said frame members including a break-up mechanism adapted to cause variations in the degree ofreciprccative movement produced by said connecting means, and a vibration dampener for said latter frame member including a counterbalance operatively connected therewith and with the means connecting the same with the correspond ing drive mean adapted to minimize the inertia forces due to reciprocation of said latter frame member.

'7. In a lens grinding machine of the kind hav ing a shiftable carrier for one element of a lens grinding couple, and means for vibrating said carrier with an automatic cyclic variation of the length of stroke imparted to said carrier by said mechanism, the combination of a counterbalance member for said carrier supported independently of said carrier and positively shiftable by said power means in a direction substantially opposed to the direction of movement of the carrier on each stroke of the carrier and to an extent in a direct ratio to the extent of the simultaneous carrier stroke, and means to yieldingly oppose the latter partof each stroke of the shiftable counterweight and carrier.

8. In a lens grinding machine. a shiftable carrier for one element of a lens-grinding couple,

an oppositely shiftable counterbalance member for said carrier, said carrier and member being supported for movement in paths having the same general direction, actuating means for positively vibrating the carrier and counterbalance member in their respective paths with a corresponding and automatic cyclic variation of the length of stroke imparted to the carrier and member by said actuating means and with said carrier moving during each stroke thereof in a direction substantially opposed to the direction of movement of said member, and means connecting the carrier and member including an extensible and compressible spring arranged to be respectively extended and compressed at opposite ends of each stroke of the carrier and member and to be free from stress substantially medially of each stroke of the carrier and member, whereby said member and said last-mentioned connection substantially neutralize the tendency of the vibratory motion of the carrier to set up vibrations in the machine.

9. In a machine having a vibratory element and, actuating means therefor, vibration dampening means comprising, in combination, a counterbalance member supported independently of said element for vibration in a path having substantially the same general direction as the path of vibratory movement of said element, means for positively moving said member in said path during each stroke of said element and in a direction substantially opposed to the direction of movement of the element, and means for yieldingly resisting the latter part of each stroke of the element and member. I

10.In-a machine having a vibratory element and actuating means therefor, vibration damp ening means comprising, in combination, a counterbalance member supported independently of said element for vibration in a path having substantially the same general direction as the path of vibratory movement of said element, means to positively drive said counterbalance member substantially oppositely to said element throughout each stroke imparted to said element by its actuating means, and means forming a constantly maintained resiliently expansible and compressible connection between said element and member for opposing with increasing force the positive drive of said element and member during the final part of each stroke of the element and member and for aiding with diminishing force the positive drive of said element and memher during the initial part of each stroke of the element and member.

11. The combination with a vibratively operable element, of a counterweight element therefor supported independently of said vibratively operable element, means to positively move said elements simultaneously in substantially opposed directions through repeated cycles of vibration of the elements, and a compressible and expansible spring constantly connected with both of said elements to augment with diminishing force the initial part of each stroke of said elements and to resist with increasing force the final part of each stroke of said elements, whereby the tendency of vibrative operation of the vibratively operable element to set up shocks is substantially neutralized.

12. The combination with an element to be vibrated, of a counterweight element therefor supported independently thereof, actuating means to positively vibrate said elements with a cyclic variation of stroke length, said means driving the two elements simultaneously in substantially opposed directions during each stroke of the respective elements through extents in direct ratio to each other, and a compressible and extensible spring constantly connected with both of said elements respectively to oppose and aid the force exerted by said actuating means on said elements during respectively the final and initial parts of the vibratory strokes of the elements.

ELI M. LONG. 

